Electroactive materials are a recently developed technology that is sometimes used as a transducer that converts electrical energy to mechanical work. Electroactive materials have advantages over other materials used in transducers. For example, electroactive materials are elastically deformable and can therefore dampen vibrations. As a result, devices using electroactive materials generate less noise. Electroactive materials are also less dense than, for example, steel. Components fabricated with electroactive materials can therefore be lighter than comparable components fabricated with steel. The electroactive materials can also be less expensive and easier to manufacture than other materials. Electroactive materials can be fabricated in a variety of form factors and easily scaled in manufacturing. These and other advantages have driven the recent development of electroactive materials, such as devices that actuate.
Devices 10 using electroactive material can be arranged with, for example, dielectric deformable material 12 between two electrodes 14 as shown in FIG. 1a. A voltage 15 can be applied to the two electrodes 14 to cause the dielectric deformable material 12 to contract. This causes the distance between the electrodes 14 to decrease. This decrease in distance is shown in FIG. 1b. Using this principle, dielectric deformable materials have been used to replace components in fluid control devices. For example, stack actuators were developed that can replace a cam-spring system. The stack actuator can be comprised of partial ring electrodes that are stacked intermittently with discs of dielectric deformable material. The stack actuator can be coupled to and displace a valve member in a poppet valve rather than the cam-spring system.
Electroactive materials have also been used to form other fluid control devices. However, such devices are not part of a fluid control system that is suited for scalability required by many industrial applications. For example, the fluid control devices may not be assembled in a modular manner with other fluid control devices to increase the available fluid processing capacity. The designs of these devices are also narrowly tailored for specific applications which limit the available market. The designs can also require complex assembly processes or multiple different components that are not well suited to be modified for particular fluid control functions. For example, a design for a prior art valve might not be easily modified into a pump design. This can increase the design costs. With respect to manufacturing, complex and prototypical designs utilizing the electroactive materials typically have high manufacturing costs and low reliability that are unsuited for large scale manufacturing. In other words, prior art fluid control device designs have not fully exploited the advantages of available with electroactive materials.
Accordingly, there is a need for an electroactive material fluid control apparatus that is scalable, inexpensive, and reliable.